README

A TYPO3 extension for sending emails via Microsoft Exchange 365 using the MS Graph API instead of SMTP. Uses OAuth 2.0 client credentials flow for secure, token-based authentication.

Features

• Send emails through Microsoft Graph API — no SMTP required
• OAuth 2.0 client credentials flow for server-to-server authentication
• Supports both backend (environment variables / TYPO3 settings) and frontend (TypoScript) configuration
• Compatible with Powermail, TYPO3 Form Framework, and other form extensions
• Optional saving of sent emails to the sender's "Sent Items" folder
• Automatic credential blinding in TYPO3's configuration module
• Works with shared mailboxes and Application Access Policies
• Send As / Send On Behalf — optional graphSenderUserId decouples the Graph mailbox used for /users/{id}/sendMail from the visible From header, so a configured mailbox can send on behalf of another

Requirements

• TYPO3: 12.4 LTS, 13.4 LTS, or 14.x
• PHP: 8.1 – 8.5
• Dependencies:
  • microsoft/microsoft-graph ^2
  • oliverkroener/ok-typo3-helper ^3

Installation

Install via Composer (recommended):

composer require oliverkroener/ok-exchange365-mailer

Local path repository

If using a local path (e.g., in a monorepo), add the repository to your root composer.json:

{
    "repositories": [
        {
            "type": "path",
            "url": "packages/ok_exchange365_mailer"
        }
    ]
}

Then install:

composer require oliverkroener/ok-exchange365-mailer:@dev

Configuration

1. Register an Azure App

Register an application in Microsoft Entra ID (formerly Azure AD) with Mail.Send and User.ReadBasic.All application permissions. Grant admin consent. See the full Azure setup guide.

2. Configure TYPO3

Set the mail transport to Exchange365Transport and provide your Azure credentials.

Via environment variables (.env):

Via TypoScript (for frontend forms):

plugin.tx_okexchange365mailer.settings.exchange365 {
    tenantId = your-tenant-id
    clientId = your-client-id
    clientSecret = your-client-secret
    fromEmail = service@your-domain.com
    # Optional: route via a different mailbox using Send As / Send On Behalf
    # graphSenderUserId = service@your-domain.com
    saveToSentItems = 1
}

Send As / Send On Behalf

The optional graphSenderUserId (or transport_exchange365_graphSenderUserId) decouples the Graph mailbox used for the API call from the visible From address of the message:

• The Graph endpoint /users/{id}/sendMail is called against graphSenderUserId.
• The message From header still resolves through $graphMessage['from'] → fromEmail → defaultMailFromAddress, so recipients see the configured sender, not the Graph mailbox.

The configured Graph mailbox must hold Send As or Send On Behalf permission on the visible sender mailbox in Exchange. See the Microsoft Graph documentation on sending mail from another user.

When graphSenderUserId is unset (or empty), the same value resolution chain is used to pick the Graph mailbox — i.e. the visible sender also sends the message, which is the standard single-mailbox setup.

Sender Display Name

The Graph API uses the Display name configured on the mailbox in Exchange Online. TYPO3's defaultMailFromName has no effect. Configure the display name in the Microsoft 365 Admin Center or Exchange Admin Center.

Architecture

Classes/
├── Mail/Transport/
│   └── Exchange365Transport.php
└── Lowlevel/EventListener/
    └── ModifyBlindedConfigurationOptionsEventListener.php
Configuration/
├── Services.yaml
├── TCA/Overrides/sys_template.php
└── TypoScript/
    ├── constants.typoscript
    └── setup.typoscript

License

GPL-2.0-or-later

Author — Oliver Kroener

Automated. Scaled. Done.

Web3 · Cloud · Automation

Technology is only valuable when it solves a real problem. For over 30 years I've been translating between business and tech — so your investment in digitalisation doesn't stall at proof-of-concept but delivers measurable results.

• Website: oliver-kroener.de
• Web3: web3.oliver-kroener.de
• Email: ok@oliver-kroener.de
• Web3 Email: oliverkroener@ethermail.io